Got Designs?Please eMail if you want me to link to and/or post your original design. Thanks.

Circuits Designed by Dave Johnson, P.E. :

Pop Free Microphone On/Off Switch Circuit - This circuit uses a simple technique to eliminate the usual “pop” sound when an electret type microphone is switched on or off. The circuit is completely passive and will work on dynamic and electret type microphones. . . Circuit by David A. Johnson P.E.-February, 2002

FM Microphone - Here is the super NEW miracle improved "Frequency Modulation Wireless Microphone" (BUG) with added easablilty, readability and copyability. This was necessitated after the number of E-Mail questions posed by people who were confused by the layout of the project (s). Before proceeding with the interesting bits, please note __ Designed by Harry Lythall-SM0VPO

FM Microphone - A micro-transmitter is so small and sensitive, it have only 8 easy-to-get parts and can be assembled in one hour. __ Designed by Jose Pino

FM Radio Microphone with Internal Loop Antenna (Area 50) - This article began as a design guide for hyper cranial erogenic field generators, however, your primitive earth brains are completely unable to respond to erogenic fields in the 100MHz region. I personally had a brain upgrade (for purely medical purposes of course) so I am able to respond __ Contact: Charles Wenzel of Wenzel Associates, Inc.

FM Transmitter - There is no thrill like the thrill you get from operating equipment you have built yourself. if you have never built a project from a magazine before, let this be your first--you'll see how much satisfaction and fun you can have! __ Designed by Tony van Roon VA3AVR

FM Transmitter-Miniature - This miniature transmitter is easy to construct and it's transmissions can be picked up on any standard FM receiver. it has a range of up to 1/4 of a mile or more. it is great for room monitoring, baby listening, nature research, etc. L1 is 8 to 10 turns of 22 gauge hookup wire close wound around a non-conductive 1/4 inch diameter form __ Designed by Andy Wilson

FM Voice Transmitter - This miniature transmitter is easy to construct and it's transmissions can be picked up on any standard FM radio. it has a range of up to 1/4-mile (Tony van Roon's 400 meters) or more, depending on the line-of-sight, obstructions by large buildings, etc. it is great for room monitoring, baby listening, nature research, __ Designed by Tony van Roon VA3AVR

FM Wireless Mike - Low power frequency modulated transmitter using two transistors. The circuit works with 9v power supply__

High Power FM Wireless Microphone - This FM Wireless Microphone has been a very popular project with beginners and experienced constructors alike. it has been used inside guitars and as the basis of a remote control system. I do however, receive many requests for a higher powered circuit and better microphone sensitivity. This High Power FM Wireless Microphone has a better frequency stability, over 1 Km range and is good on microphone sensitivity. This has been achieved by adding an RF amplifier buffer (with 10dB gain) and an AF preamplifier to boost the modulation a little.__

Micro Spy with TTL - This circuit is old (70's) but since the 74LS13 is from the regular 74xx series and easy to obtain, I decided to keep the circuit in place until components are no longer available. Not much to tell here. Performance is based on the 74LS13, a 'Dual 4-input Positive-Nand Schmitt Trigger'. This circuit was experimental and so has no real purpose other than tinkering. __ Designed by Tony van Roon VA3AVR

Miniature FM Transmitter - This miniature transmitter is easy to construct and it's transmissions can be picked up on any standard FM receiver. it has a range of up to 1/4 of a mile or more. it is great for room monitoring, baby listening, nature research, etc. L1 is 8 to 10 turns of 22 gauge hookup wire close wound around a non-conductive 1/4 inch diameter form __ Designed by Andy Wilson

Miniature FM Transmitter #1 - This miniature transmitter is easy to construct and it's transmissions can be picked up on any standard FM radio. it has a range of up to 1/4-mile (Tony van Roon's 400 meters) or more, depending on the line-of-sight, obstructions by large buildings, etc. it is great for room monitoring, baby listening, nature research, __ Designed by Tony van Roon VA3AVR

Miniature FM Transmitter #7 - There is no thrill like the thrill you get from operating equipment you have built yourself. if you have never built a project from a magazine before, let this be your first--you'll see how much satisfaction and fun you can have! __ Designed by Tony van Roon VA3AVR

Pop Free Microphone On/Off Switch Circuit - This circuit uses a simple technique to eliminate the usual “pop” sound when an electret type microphone is switched on or off. The circuit is completely passive and will work on dynamic and electret type microphones. . . Circuit by David A. Johnson P.E.-February, 2002

Simple Circuit Wireless Microphone - This wireless FM microphone is simple to build and it has a useful transmitting range (over 300 meters in the open air). Despite its small component count and a 3V operating voltage it will easily penetrate over three floors of an apartment building. it may be tuned anywhere in the FM band (87-108MHz) and its transmissions can be picked up on any standard FM receiver.__ hobbyteam @ hobby-hour.com

Simple FM Transmitter - There is no thrill like the thrill you get from operating equipment you have built yourself. if you have never built a project from a magazine before, let this be your first--you'll see how much satisfaction and fun you can have! __ Designed by Tony van Roon VA3AVR

Super Spy Transmitter Bug - A very small home made FM transmitter Bug using a single transistor and with a transmission range of 200 meters. This FM transmitter Bug is very easy to build. The size of the circuit board is ONLY 22mm x 10mm.__

Wireless Microphone FM Transmitter - This Wireless Microphone FM Transmitter has been a very popular project with beginners and experienced constructors alike. it has been used inside guitars and as the basis of a remote control system. I do however, receive many requests for a higher powered circuit and better microphone sensitivity. Now I can introduce the new FM Wireless Microphone, which also has a better frequency stability, over 1Km range (under ideal conditions) and is good on microphone sensitivity. This has been achieved by adding an RF amplifier buffer (with 10dB gain) and an AF preamplifier to boost the modulation a little.__